We report an ethnographic and field-experiment-based study of time intervals in Amondawa, a Tupi language and culture of Amazonia. We analyse two Amondawa time interval systems based on natural environmental events (seasons and days), as well as the Amondawa system for categorising lifespan time (&#8220;age&#8221;). Amondawa time intervals are exclusively event-based, as opposed to time-based (i.e. they are based on event-duration, rather than measured abstract time units). Amondawa has no lexicalised abstract concept of time and no practices of time reckoning, as conventionally understood in the anthropological literature. Our findings indicate that not only are time interval systems and categories linguistically and culturally specific, but that they do not depend upon a universal &#8220;concept of time&#8221;. We conclude that the abstract conceptual domain of time is not a human cognitive universal, but a cultural historical construction, semiotically mediated by symbolic and cultural-cognitive artefacts for time reckoning.